[hobbit] some larrd issues on hobbit 4.0.3 rc1

OK --

Re-ordering the AIX and linux entries in do_vmstat.c and copying the vmstat rrds from my other BB system fixed the problem. Thanks for the help.

And the do_disk.c patch is MUCH appreciated! I'm down to nine disk graphs on my R3 db server (and it has two clones that will be affected as well)

Thanks!

Tom